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<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE chapter PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
<chapter id="Big500users">
<title>The 500-User Office</title>
<para>
The Samba-3 networking you explored in <link linkend="secure"/> covers the finer points of
configuration of peripheral services such as DHCP and DNS, and WINS. You experienced
implementation of a simple configuration of the services that are important adjuncts
to successful deployment of Samba.
</para>
<para>
An analysis of the history of postings to the Samba mailing list easily demonstrates
that the two most prevalent Samba problem areas are
</para>
<itemizedlist>
<listitem><para>
Defective resolution of a NetBIOS name to its IP address
</para></listitem>
<listitem><para>
Printing problems
</para></listitem>
</itemizedlist>
<para>
The exercises
so far in this book have focused on implementation of the simplest printing processes
involving no print job processing intelligence. In this chapter, you maintain
that same approach to printing, but <link linkend="happy"/> presents an opportunity
to make printing more complex for the administrator while making it easier for the user.
</para>
<para>
<indexterm><primary>WINS server</primary></indexterm>
<indexterm><primary>tdbsam</primary></indexterm>
<indexterm><primary>passdb backend</primary></indexterm>
<link linkend="secure"/> demonstrates operation of a DHCP server and a DNS server
as well as a central WINS server. You validated the operation of these services and
saw an effective implementation of a Samba domain controller using the
<parameter>tdbsam</parameter> passdb backend.
</para>
<para>
The objective of this chapter is to introduce more complex techniques that can be used to
improve manageability of Samba as networking needs grow. In this chapter, you implement
a distributed DHCP server environment, a distributed DNS server arrangement, a centralized
WINS server, and a centralized Samba domain controller.
</para>
<para>
A note of caution is important regarding the Samba configuration that is used in this
chapter. The use of a single domain controller on a routed, multisegment network is
a poor design choice that leads to potential network user complaints.
This chapter demonstrates some successful
techniques in deployment and configuration management. This should be viewed as a
foundation chapter for complex Samba deployments.
</para>
<para>
As you master the techniques presented here, you may find much better methods to
improve network management and control while reducing human resource overheads.
You should take the opportunity to innovate and expand on the methods presented
here and explore them to the fullest.
</para>
<sect1>
<title>Introduction</title>
<para>
Business continues to go well for Abmas. Mr. Meany is driving your success and the
network continues to grow thanks to the hard work Christine has done. You recently
hired Stanley Soroka as manager of information systems. Christine recommended Stan
to the role. She told you Stan is so good at handling Samba that he can make a cast
iron rocking horse that is embedded in concrete kick like a horse at a rodeo. You
need skills like his. Christine and Stan get along just fine. Let's see what
you can get out of this pair as they plot the next-generation networks.
</para>
<para>
Ten months ago Abmas closed an acquisition of a property insurance business. The
founder lost interest in the business and decided to sell it to Mr. Meany. Because
they were former university classmates, the purchase was concluded with mutual assent.
The acquired business is located at the other end of town in much larger facilities.
The old Abmas building has become too small. Located on the same campus as the newly
acquired business are two empty buildings that are ideal to provide Abmas with
opportunity for growth.
</para>
<para>
Abmas has now completed the purchase of the two empty buildings, and you are
to install a new network and relocate staff in nicely furnished new facilities.
The new network is to be used to fully integrate company operations. You have
decided to locate the new network operations control center in the larger building
in which the insurance group is located to take advantage of an ideal floor space
and to allow Stan and Christine to fully stage the new network and test it before
it is rolled out. Your strategy is to complete the new network so that it
is ready for operation when the old office moves into the new premises.
</para>
<sect2>
<title>Assignment Tasks</title>
<para>
The acquired business had 280 network users. The old Abmas building housed
220 network users in unbelievably cramped conditions. The network that
initially served 130 users now handles 220 users quite well.
</para>
<para>
The two businesses will be fully merged to create a single campus company.
The Property Insurance Group (PIG) houses 300 employees, the new Accounting
Services Group (ASG) will be in a small building (BLDG1) that houses 50
employees, and the Financial Services Group (FSG) will be housed in a large
building that has capacity for growth (BLDG2). Building 2 houses 150 network
users.
</para>
<para>
You have decided to connect the building using fiber optic links between new
routers. As a backup, the buildings are interconnected using line-of-sight
high-speed infrared facilities. The infrared connection provides a
secondary route to be used during periods of high demand for network
bandwidth.
</para>
<para>
The Internet gateway is upgraded to 15 Mb/sec service. Your ISP
provides on your premises a fully managed Cisco PIX firewall. You no longer need
to worry about firewall facilities on your network.
</para>
<para>
Stanley and Christine have purchased new server hardware. Christine wants to
roll out a network that has whistles and bells. Stan wants to start off with
a simple to manage, not-too-complex network. He believes that network
users need to be gradually introduced to new features and capabilities and not
rushed into an environment that may cause disorientation and loss of productivity.
</para>
<para>
Your intrepid network team has decided to implement a network configuration
that closely mirrors the successful system you installed in the old Abmas building.
The new network infrastructure is owned by Abmas, but all desktop systems
are being procured through a new out-source services and leasing company. Under
the terms of a deal with Mr. M. Proper (CEO), DirectPointe, Inc., provides
all desktop systems and includes full level-one help desk support for
a flat per-machine monthly fee. The deal allows you to add workstations on demand.
This frees Stan and Christine to deal with deeper issues as they emerge and
permits Stan to work on creating new future value-added services.
</para>
<para>
DirectPointe Inc. receives from you a new standard desktop configuration
every four months. They automatically roll that out to each desktop system.
You must keep DirectPointe informed of all changes.
</para>
<para><indexterm>
<primary>PDC</primary>
</indexterm>
The new network has a single Samba Primary Domain Controller (PDC) located in the
Network Operation Center (NOC). Buildings 1 and 2 each have a local server
for local application servicing. It is a domain member. The new system
uses the <parameter>tdbsam</parameter> passdb backend.
</para>
<para>
Printing is based on raw pass-through facilities just as it has been used so far.
All printer drivers are installed on the desktop and notebook computers.
</para>
</sect2>
</sect1>
<sect1>
<title>Dissection and Discussion</title>
<para>
<indexterm><primary>network load factors</primary></indexterm>
The example you are building in this chapter is of a network design that works, but this
does not make it a design that is recommended. As a general rule, there should be at least
one Backup Domain Controller (BDC) per 150 Windows network clients. The principle behind
this recommendation is that correct operation of MS Windows clients requires rapid
network response to all SMB/CIFS requests. The same rule says that if there are more than
50 clients per domain controller, they are too busy to service requests. Let's put such
rules aside and recognize that network load affects the integrity of domain controller
responsiveness. This network will have 500 clients serviced by one central domain
controller. This is not a good omen for user satisfaction. You, of course, address this
very soon (see <link linkend="happy"/>).
</para>
<sect2>
<title>Technical Issues</title>
<para>
Stan has talked you into a horrible compromise, but it is addressed. Just make
certain that the performance of this network is well validated before going live.
</para>
<para>
Design decisions made in this design include the following:
</para>
<itemizedlist>
<listitem><para>
<indexterm><primary>PDC</primary></indexterm>
<indexterm><primary>LDAP</primary></indexterm>
<indexterm><primary>identity management</primary></indexterm>
A single PDC is being implemented. This limitation is based on the choice not to
use LDAP. Many network administrators fear using LDAP because of the perceived
complexity of implementation and management of an LDAP-based backend for all user
identity management as well as to store network access credentials.
</para></listitem>
<listitem><para>
<indexterm><primary>BDC</primary></indexterm>
<indexterm><primary>machine secret password</primary></indexterm>
Because of the refusal to use an LDAP (ldapsam) passdb backend at this time, the
only choice that makes sense with 500 users is to use the tdbsam passwd backend.
This type of backend is not receptive to replication to BDCs. If the tdbsam
<filename>passdb.tdb</filename> file is replicated to BDCs using
<command>rsync</command>, there are two potential problems: (1) data that is in
memory but not yet written to disk will not be replicated, and (2) domain member
machines periodically change the secret machine password. When this happens, there
is no mechanism to return the changed password to the PDC.
</para></listitem>
<listitem><para>
All domain user, group, and machine accounts are managed on the PDC. This makes
for a simple mode of operation but has to be balanced with network performance and
integrity of operations considerations.
</para></listitem>
<listitem><para>
<indexterm><primary>WINS</primary></indexterm>
A single central WINS server is being used. The PDC is also the WINS server.
Any attempt to operate a routed network without a WINS server while using NetBIOS
over TCP/IP protocols does not work unless on each client the name resolution
entries for the PDC are added to the <filename>LMHOSTS</filename>. This file is
normally located on the Windows XP Professional client in the
<filename>C:\WINDOWS\SYSTEM32\ETC\DRIVERS</filename> directory.
</para></listitem>
<listitem><para>
At this time the Samba WINS database cannot be replicated. That is
why a single WINS server is being implemented. This should work without a problem.
</para></listitem>
<listitem><para>
<indexterm><primary>winbindd</primary></indexterm>
BDCs make use of <command>winbindd</command> to provide
access to domain security credentials for file system access and object storage.
</para></listitem>
<listitem><para>
<indexterm><primary>DHCP</primary><secondary>relay</secondary></indexterm>
<indexterm><primary>DHCP</primary><secondary>requests</secondary></indexterm>
Configuration of Windows XP Professional clients is achieved using DHCP. Each
subnet has its own DHCP server. Backup DHCP serving is provided by one
alternate DHCP server. This necessitates enabling of the DHCP Relay agent on
all routers. The DHCP Relay agent must be programmed to pass DHCP Requests from the
network directed at the backup DHCP server.
</para></listitem>
<listitem><para>
All network users are granted the ability to print to any printer that is
network-attached. All printers are available from each server. Print jobs that
are spooled to a printer that is not on the local network segment are automatically
routed to the print spooler that is in control of that printer. The specific details
of how this might be done are demonstrated for one example only.
</para></listitem>
<listitem><para>
The network address and subnetmask chosen provide 1022 usable IP addresses in
each subnet. If in the future more addresses are required, it would make sense
to add further subnets rather than change addressing.
</para></listitem>
</itemizedlist>
</sect2>
<sect2>
<title>Political Issues</title>
<para>
This case gets close to the real world. You and I know the right way to implement
domain control. Politically, we have to navigate a minefield. In this case, the need is to
get the PDC rolled out in compliance with expectations and also to be ready to save the day
by having the real solution ready before it is needed. That real solution is presented in
<link linkend="happy"/>.
</para>
</sect2>
</sect1>
<sect1>
<title>Implementation</title>
<para>
The following configuration process begins following installation of Red Hat Fedora Core2 on the
three servers shown in the network topology diagram in <link linkend="chap05net"/>. You have
selected hardware that is appropriate to the task.
</para>
<figure id="chap05net">
<title>Network Topology &smbmdash; 500 User Network Using tdbsam passdb backend.</title>
<imagefile scale="50">chap5-net</imagefile>
</figure>
<sect2 id="ch5-dnshcp-setup">
<title>Installation of DHCP, DNS, and Samba Control Files</title>
<para>
Carefully install the configuration files into the correct locations as shown in
<link linkend="ch5-filelocations"/>. You should validate that the full file path is
correct as shown.
</para>
<para>
The abbreviation shown in this table as <constant>{VLN}</constant> refers to
the directory location beginning with <filename>/var/lib/named</filename>.
</para>
<table id="ch5-filelocations"><title>Domain: <constant>MEGANET</constant>, File Locations for Servers</title>
<tgroup cols="5">
<colspec colname='c1' align="left"/>
<colspec colname='c2' align="left"/>
<colspec colname='c3' align="center"/>
<colspec colname='c4' align="center"/>
<colspec colname='c5' align="center"/>
<thead>
<row>
<entry align="center" namest='c1' nameend='c2'>File Information</entry>
<entry align="center" namest="c3" nameend="c5">Server Name</entry>
</row>
<row>
<entry align="center">Source</entry>
<entry align="center">Target Location</entry>
<entry align="center">MASSIVE</entry>
<entry align="center">BLDG1</entry>
<entry align="center">BLDG2</entry>
</row>
</thead>
<tbody>
<row>
<entry><link linkend="ch5-massivesmb"/></entry>
<entry><filename>/etc/samba/smb.conf</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="ch5-dc-common"/></entry>
<entry><filename>/etc/samba/dc-common.conf</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="ch5-commonsmb"/></entry>
<entry><filename>/etc/samba/common.conf</filename></entry>
<entry>Yes</entry>
<entry>Yes</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="ch5-bldg1-smb"/></entry>
<entry><filename>/etc/samba/smb.conf</filename></entry>
<entry>No</entry>
<entry>Yes</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="ch5-bldg2-smb"/></entry>
<entry><filename>/etc/samba/smb.conf</filename></entry>
<entry>No</entry>
<entry>No</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="ch5-dommem-smb"/></entry>
<entry><filename>/etc/samba/dommem.conf</filename></entry>
<entry>No</entry>
<entry>Yes</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="massive-dhcp"/></entry>
<entry><filename>/etc/dhcpd.conf</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="bldg1dhcp"/></entry>
<entry><filename>/etc/dhcpd.conf</filename></entry>
<entry>No</entry>
<entry>Yes</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="bldg2dhcp"/></entry>
<entry><filename>/etc/dhcpd.conf</filename></entry>
<entry>No</entry>
<entry>No</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="massive-nameda"/></entry>
<entry><filename>/etc/named.conf (part A)</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="massive-namedb"/></entry>
<entry><filename>/etc/named.conf (part B)</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="massive-namedc"/></entry>
<entry><filename>/etc/named.conf (part C)</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="abmasbizdns"/></entry>
<entry><filename>{VLN}/master/abmas.biz.hosts</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="abmasusdns"/></entry>
<entry><filename>{VLN}/master/abmas.us.hosts</filename></entry>
<entry>Yes</entry>
<entry>No</entry>
<entry>No</entry>
</row>
<row>
<entry><link linkend="bldg12nameda"/></entry>
<entry><filename>/etc/named.conf (part A)</filename></entry>
<entry>No</entry>
<entry>Yes</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="bldg12namedb"/></entry>
<entry><filename>/etc/named.conf (part B)</filename></entry>
<entry>No</entry>
<entry>Yes</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="loopback"/></entry>
<entry><filename>{VLN}/localhost.zone</filename></entry>
<entry>Yes</entry>
<entry>Yes</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="dnsloopy"/></entry>
<entry><filename>{VLN}/127.0.0.zone</filename></entry>
<entry>Yes</entry>
<entry>Yes</entry>
<entry>Yes</entry>
</row>
<row>
<entry><link linkend="roothint"/></entry>
<entry><filename>{VLN}/root.hint</filename></entry>
<entry>Yes</entry>
<entry>Yes</entry>
<entry>Yes</entry>
</row>
</tbody>
</tgroup>
</table>
</sect2>
<sect2>
<title>Server Preparation: All Servers</title>
<para>
The following steps apply to all servers. Follow each step carefully.
</para>
<procedure>
<title>Server Preparation Steps</title>
<step><para>
Using the UNIX/Linux system tools, set the name of the server as shown in the network
topology diagram in <link linkend="chap05net"/>. For SUSE Linux products, the tool
that permits this is called <command>yast2</command>; for Red Hat Linux products,
you can use the <command>netcfg</command> tool.
Verify that your hostname is correctly set by running:
<screen>
&rootprompt; uname -n
</screen>
An alternate method to verify the hostname is:
<screen>
&rootprompt; hostname -f
</screen>
</para></step>
<step><para>
<indexterm><primary>/etc/hosts</primary></indexterm>
<indexterm><primary>named</primary></indexterm>
Edit your <filename>/etc/hosts</filename> file to include the primary names and addresses
of all network interfaces that are on the host server. This is necessary so that during
startup the system is able to resolve all its own names to the IP address prior to
startup of the DNS server. You should check the startup order of your system. If the
CUPS print server is started before the DNS server (<command>named</command>), you
should also include an entry for the printers in the <filename>/etc/hosts</filename> file.
</para></step>
<step><para>
<indexterm><primary>/etc/resolv.conf</primary></indexterm>
All DNS name resolution should be handled locally. To ensure that the server is configured
correctly to handle this, edit <filename>/etc/resolv.conf</filename> so it has the following
content:
<screen>
search abmas.us abmas.biz
nameserver 127.0.0.1
</screen>
This instructs the name resolver function (when configured correctly) to ask the DNS server
that is running locally to resolve names to addresses.
</para></step>
<step><para>
<indexterm><primary>administrator</primary></indexterm>
<indexterm><primary>smbpasswd</primary></indexterm>
Add the <constant>root</constant> user to the password backend:
<screen>
&rootprompt; smbpasswd -a root
New SMB password: XXXXXXXX
Retype new SMB password: XXXXXXXX
&rootprompt;
</screen>
The <constant>root</constant> account is the UNIX equivalent of the Windows domain administrator.
This account is essential in the regular maintenance of your Samba server. It must never be
deleted. If for any reason the account is deleted, you may not be able to recreate this account
without considerable trouble.
</para></step>
<step><para>
<indexterm><primary>username map</primary></indexterm>
<indexterm><primary>/etc/samba/smbusers</primary></indexterm>
Create the username map file to permit the <constant>root</constant> account to be called
<constant>Administrator</constant> from the Windows network environment. To do this, create
the file <filename>/etc/samba/smbusers</filename> with the following contents:
<screen>
####
# User mapping file
####
# File Format
# -----------
# Unix_ID = Windows_ID
#
# Examples:
# root = Administrator
# janes = "Jane Smith"
# jimbo = Jim Bones
#
# Note: If the name contains a space it must be double quoted.
# In the example above the name 'jimbo' will be mapped to Windows
# user names 'Jim' and 'Bones' because the space was not quoted.
#######################################################################
root = Administrator
####
# End of File
####
</screen>
</para></step>
<step><para>
Configure all network-attached printers to have a fixed IP address.
</para></step>
<step><para>
Create an entry in the DNS database on the server <constant>MASSIVE</constant>
in both the forward lookup database for the zone <constant>abmas.biz.hosts</constant>
and in the reverse lookup database for the network segment that the printer is
located in. Example configuration files for similar zones were presented in <link linkend="secure"/>,
<link linkend="abmasbiz"/> and <link linkend="eth2zone"/>.
</para></step>
<step><para>
Follow the instructions in the printer manufacturer's manuals to permit printing
to port 9100. Use any other port the manufacturer specifies for direct mode,
raw printing. This allows the CUPS spooler to print using raw mode protocols.
<indexterm><primary>CUPS</primary></indexterm>
<indexterm><primary>raw printing</primary></indexterm>
</para></step>
<step><para>
<indexterm><primary>CUPS</primary><secondary>queue</secondary></indexterm>
Only on the server to which the printer is attached configure the CUPS Print
Queues as follows:
<screen>
&rootprompt; lpadmin -p <parameter>printque</parameter> -v socket://<parameter>printer-name</parameter>.abmas.biz:9100 -E
</screen>
<indexterm><primary>print filter</primary></indexterm>
This step creates the necessary print queue to use no assigned print filter. This
is ideal for raw printing, that is, printing without use of filters.
The name <parameter>printque</parameter> is the name you have assigned for
the particular printer.
</para></step>
<step><para>
Print queues may not be enabled at creation. Make certain that the queues
you have just created are enabled by executing the following:
<screen>
&rootprompt; /usr/bin/enable <parameter>printque</parameter>
</screen>
</para></step>
<step><para>
Even though your print queue may be enabled, it is still possible that it
does not accept print jobs. A print queue services incoming printing
requests only when configured to do so. Ensure that your print queue is
set to accept incoming jobs by executing the following command:
<screen>
&rootprompt; /usr/bin/accept <parameter>printque</parameter>
</screen>
</para></step>
<step><para>
<indexterm><primary>mime type</primary></indexterm>
<indexterm><primary>/etc/mime.convs</primary></indexterm>
<indexterm><primary>application/octet-stream</primary></indexterm>
This step, as well as the next one, may be omitted where CUPS version 1.1.18
or later is in use. Although it does no harm to follow it anyway, and may
help to avoid time spent later trying to figure out why print jobs may be
disappearing without a trace. Look at these two steps as <emphasis>insurance</emphasis>
against lost time. Edit file <filename>/etc/cups/mime.convs</filename> to
uncomment the line:
<screen>
application/octet-stream application/vnd.cups-raw 0 -
</screen>
</para></step>
<step><para>
<indexterm><primary>/etc/mime.types</primary></indexterm>
Edit the file <filename>/etc/cups/mime.types</filename> to uncomment the line:
<screen>
application/octet-stream
</screen>
</para></step>
<step><para>
Refer to the CUPS printing manual for instructions regarding how to configure
CUPS so that print queues that reside on CUPS servers on remote networks
route print jobs to the print server that owns that queue. The default setting
on your CUPS server may automatically discover remotely installed printers and
may permit this functionality without requiring specific configuration.
</para></step>
<step><para>
As part of the roll-out program, you need to configure the application's
server shares. This can be done once on the central server and may then be
replicated using a tool such as <command>rsync</command>. Refer to the man
page for <command>rsync</command> for details regarding use. The notes in
<link linkend="ch4appscfg"/> may help in your decisions to use an application
server facility.
</para></step>
</procedure>
<note><para>
Logon scripts that are run from a domain controller (PDC or BDC) are capable of using semi-intelligent
processes to automap Windows client drives to an application server that is nearest to the client. This
is considerably more difficult when a single PDC is used on a routed network. It can be done, but not
as elegantly as you see in the next chapter.
</para></note>
</sect2>
<sect2>
<title>Server-Specific Preparation</title>
<para>
There are some steps that apply to particular server functionality only. Each step is critical
to correct server operation. The following step-by-step installation guidance will assist you
in working through the process of configuring the PDC and then both BDC's.
</para>
<sect3>
<title>Configuration for Server: <constant>MASSIVE</constant></title>
<para>
The steps presented here attempt to implement Samba installation in a generic manner. While
some steps are clearly specific to Linux, it should not be too difficult to apply them to
your platform of choice.
</para>
<procedure>
<title>Primary Domain Controller Preparation</title>
<step><para>
<indexterm><primary>/etc/rc.d/boot.local</primary></indexterm>
<indexterm><primary>IP forwarding</primary></indexterm>
The host server acts as a router between the two internal network segments as well
as for all Internet access. This necessitates that IP forwarding be enabled. This can be
achieved by adding to the <filename>/etc/rc.d/boot.local</filename> an entry as follows:
<screen>
echo 1 > /proc/sys/net/ipv4/ip_forward
</screen>
To ensure that your kernel is capable of IP forwarding during configuration, you may wish to execute
that command manually also. This setting permits the Linux system to act as a router.
</para></step>
<step><para>
This server is dual hosted (i.e., has two network interfaces) &smbmdash; one goes to the Internet
and the other to a local network that has a router that is the gateway to the remote networks.
You must therefore configure the server with route table entries so that it can find machines
on the remote networks. You can do this using the appropriate system tools for your Linux
server or using static entries that you place in one of the system startup files. It is best
to always use the tools that the operating system vendor provided. In the case of SUSE Linux, the
best tool to do this is YaST (refer to SUSE Administration Manual); in the case of Red Hat,
this is best done using the graphical system configuration tools (see the Red Hat documentation).
An example of how this may be done manually is as follows:
<screen>
&rootprompt; route add net 172.16.4.0 netmask 255.255.252.0 gw 172.16.0.128
&rootprompt; route add net 172.16.8.0 netmask 255.255.252.0 gw 172.16.0.128
</screen>
If you just execute these commands manually, the route table entries you have created are
not persistent across system reboots. You may add these commands directly to the local
startup files as follows: (SUSE) <filename>/etc/rc.d/boot.local</filename>, (Red Hat)
<filename>/etc/rc.d/init.d/rc.local</filename>.
</para></step>
<step><para>
<indexterm><primary>/etc/nsswitch.conf</primary></indexterm>
The final step that must be completed is to edit the <filename>/etc/nsswitch.conf</filename> file.
This file controls the operation of the various resolver libraries that are part of the Linux
Glibc libraries. Edit this file so that it contains the following entries:
<screen>
hosts: files dns wins
</screen>
</para></step>
<step><para>
<indexterm><primary>initGrps.sh</primary></indexterm>
Create and map Windows domain groups to UNIX groups. A sample script is provided in
<link linkend="ch5-initgrps"/>. Create a file containing this script. You called yours
<filename>/etc/samba/initGrps.sh</filename>. Set this file so it can be executed
and then execute the script. An example of the execution of this script as well as its
validation are shown in Section 4.3.2, Step 5.
</para></step>
<step><para>
<indexterm><primary>/etc/passwd</primary></indexterm>
<indexterm><primary>password</primary><secondary>backend</secondary></indexterm>
<indexterm><primary>smbpasswd</primary></indexterm>
For each user who needs to be given a Windows domain account, make an entry in the
<filename>/etc/passwd</filename> file as well as in the Samba password backend.
Use the system tool of your choice to create the UNIX system account, and use the Samba
<command>smbpasswd</command> to create a domain user account.
</para>
<para>
<indexterm><primary>useradd</primary></indexterm>
<indexterm><primary>adduser</primary></indexterm>
<indexterm><primary>user</primary><secondary>management</secondary></indexterm>
There are a number of tools for user management under UNIX, such as
<command>useradd</command>, <command>adduser</command>, as well as a plethora of custom
tools. With the tool of your choice, create a home directory for each user.
</para></step>
<step><para>
Using the preferred tool for your UNIX system, add each user to the UNIX groups created
previously as necessary. File system access control is based on UNIX group membership.
</para></step>
<step><para>
Create the directory mount point for the disk subsystem that is to be mounted to provide
data storage for company files, in this case, the mount point indicated in the &smb.conf;
file is <filename>/data</filename>. Format the file system as required and mount the formatted
file system partition using appropriate system tools.
</para></step>
<step><para>
<indexterm><primary>file system</primary>
<secondary>permissions</secondary></indexterm>
Create the top-level file storage directories for data and applications as follows:
<screen>
&rootprompt; mkdir -p /data/{accounts,finsvcs,pidata}
&rootprompt; mkdir -p /apps
&rootprompt; chown -R root:root /data
&rootprompt; chown -R root:root /apps
&rootprompt; chown -R bjordan:accounts /data/accounts
&rootprompt; chown -R bjordan:finsvcs /data/finsvcs
&rootprompt; chown -R bjordan:finsvcs /data/pidata
&rootprompt; chmod -R ug+rwxs,o-rwx /data
&rootprompt; chmod -R ug+rwx,o+rx-w /apps
</screen>
Each department is responsible for creating its own directory structure within the departmental
share. The directory root of the <command>accounts</command> share is <filename>/data/accounts</filename>.
The directory root of the <command>finsvcs</command> share is <filename>/data/finsvcs</filename>.
The <filename>/apps</filename> directory is the root of the <constant>apps</constant> share
that provides the application server infrastructure.
</para></step>
<step><para>
The &smb.conf; file specifies an infrastructure to support roaming profiles and network
logon services. You can now create the file system infrastructure to provide the
locations on disk that these services require. Adequate planning is essential
because desktop profiles can grow to be quite large. For planning purposes, a minimum of
200 MB of storage should be allowed per user for profile storage. The following
commands create the directory infrastructure needed:
<screen>
&rootprompt; mkdir -p /var/spool/samba
&rootprompt; mkdir -p /var/lib/samba/{netlogon/scripts,profiles}
&rootprompt; chown -R root:root /var/spool/samba
&rootprompt; chown -R root:root /var/lib/samba
&rootprompt; chmod a+rwxt /var/spool/samba
</screen>
For each user account that is created on the system, the following commands should be
executed:
<screen>
&rootprompt; mkdir /var/lib/samba/profiles/'username'
&rootprompt; chown 'username':users /var/lib/samba/profiles/'username'
&rootprompt; chmod ug+wrx,o+rx,-w /var/lib/samba/profiles/'username'
</screen>
</para></step>
<step><para>
<indexterm><primary>unix2dos</primary></indexterm>
<indexterm><primary>dos2unix</primary></indexterm>
Create a logon script. It is important that each line is correctly terminated with
a carriage return and line-feed combination (i.e., DOS encoding). The following procedure
works if the right tools (<constant>unxi2dos</constant> and <constant>dos2unix</constant>) are installed.
First, create a file called <filename>/var/lib/samba/netlogon/scripts/logon.bat.unix</filename>
with the following contents:
<screen>
net time \\massive /set /yes
net use h: /home
</screen>
Convert the UNIX file to a DOS file:
<screen>
&rootprompt; dos2unix &lt; /var/lib/samba/netlogon/scripts/logon.bat.unix \
&gt; /var/lib/samba/netlogon/scripts/logon.bat
</screen>
</para></step>
<step><para>
There is one preparatory step without which you cannot have a working Samba network
environment. You must add an account for each network user. You can do this by executing
the following steps for each user:
<screen>
&rootprompt; useradd -m <parameter>username</parameter>
&rootprompt; passwd <parameter>username</parameter>
Changing password for <parameter>username</parameter>.
New password: XXXXXXXX
Re-enter new password: XXXXXXXX
Password changed
&rootprompt; smbpasswd -a <parameter>username</parameter>
New SMB password: XXXXXXXX
Retype new SMB password: XXXXXXXX
Added user <parameter>username</parameter>.
</screen>
You do, of course, use a valid user login ID in place of <parameter>username</parameter>.
</para></step>
<step><para>
Follow the processes shown in <link linkend="ch5-procstart"/> to start all services.
</para></step>
<step><para>
Your server is ready for validation testing. Do not proceed with the steps in
<link linkend="ch5-domsvrspec"/> until after the operation of the server has been
validated following the same methods as outlined in <link linkend="secure"/>, <link linkend="ch4valid"/>.
</para></step>
</procedure>
</sect3>
<sect3 id="ch5-domsvrspec">
<title>Configuration Specific to Domain Member Servers: <constant>BLDG1, BLDG2</constant></title>
<para>
The following steps will guide you through the nuances of implementing BDCs for the broadcast
isolated network segments. Remember that if the target installation platform is not Linux, it may
be necessary to adapt some commands to the equivalent on the target platform.
</para>
<procedure>
<title>Backup Domain Controller Configuration Steps</title>
<step><para>
<indexterm><primary>/etc/nsswitch.conf</primary></indexterm>
The final step that must be completed is to edit the <filename>/etc/nsswitch.conf</filename> file.
This file controls the operation of the various resolver libraries that are part of the Linux
Glibc libraries. Edit this file so that it contains the following entries:
<screen>
passwd: files winbind
group: files winbind
hosts: files dns wins
</screen>
</para></step>
<step><para>
Follow the steps outlined in <link linkend="ch5-procstart"/> to start all services. Do not
start Samba at this time. Samba is controlled by the process called <command>smb</command>.
</para></step>
<step><para>
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm>
You must now attempt to join the domain member servers to the domain. The following
instructions should be executed to effect this:
<screen>
&rootprompt; net rpc join
</screen>
</para></step>
<step><para>
<indexterm><primary>service</primary><secondary>smb</secondary><tertiary>start</tertiary></indexterm>
You now start the Samba services by executing:
<screen>
&rootprompt; service smb start
</screen>
</para></step>
<step><para>
Your server is ready for validation testing. Do not proceed with the steps in
<link linkend="ch5-domsvrspec"/> until after the operation of the server has been
validated following the same methods as outlined in <link linkend="ch4valid"/>.
</para></step>
</procedure>
</sect3>
</sect2>
<!-- One -->
<example id="ch5-massivesmb">
<title>Server: MASSIVE (PDC), File: <filename>/etc/samba/smb.conf</filename></title>
<smbconfblock>
<smbconfcomment>Global parameters</smbconfcomment>
<smbconfsection name="[global]"/>
<smbconfoption name="workgroup">MEGANET</smbconfoption>
<smbconfoption name="netbios name">MASSIVE</smbconfoption>
<smbconfoption name="interfaces">eth1, lo</smbconfoption>
<smbconfoption name="bind interfaces only">Yes</smbconfoption>
<smbconfoption name="passdb backend">tdbsam</smbconfoption>
<smbconfoption name="smb ports">139</smbconfoption>
<smbconfoption name="add user script">/usr/sbin/useradd -m '%u'</smbconfoption>
<smbconfoption name="delete user script">/usr/sbin/userdel -r '%u'</smbconfoption>
<smbconfoption name="add group script">/usr/sbin/groupadd '%g'</smbconfoption>
<smbconfoption name="delete group script">/usr/sbin/groupdel '%g'</smbconfoption>
<smbconfoption name="add user to group script">/usr/sbin/usermod -G '%g' '%u'</smbconfoption>
<smbconfoption name="add machine script">/usr/sbin/useradd -s /bin/false -d /var/lib/nobody '%u'</smbconfoption>
<smbconfoption name="preferred master">Yes</smbconfoption>
<smbconfoption name="wins support">Yes</smbconfoption>
<smbconfoption name="include">/etc/samba/dc-common.conf</smbconfoption>
<smbconfsection name="[accounts]"/>
<smbconfoption name="comment">Accounting Files</smbconfoption>
<smbconfoption name="path">/data/accounts</smbconfoption>
<smbconfoption name="read only">No</smbconfoption>
<smbconfsection name="[service]"/>
<smbconfoption name="comment">Financial Services Files</smbconfoption>
<smbconfoption name="path">/data/service</smbconfoption>
<smbconfoption name="read only">No</smbconfoption>
<smbconfsection name="[pidata]"/>
<smbconfoption name="comment">Property Insurance Files</smbconfoption>
<smbconfoption name="path">/data/pidata</smbconfoption>
<smbconfoption name="read only">No</smbconfoption>
</smbconfblock>
</example>
<!-- Two -->
<example id="ch5-dc-common">
<title>Server: MASSIVE (PDC), File: <filename>/etc/samba/dc-common.conf</filename></title>
<smbconfblock>
<smbconfcomment>Global parameters</smbconfcomment>
<smbconfsection name="[global]"/>
<smbconfoption name="shutdown script">/var/lib/samba/scripts/shutdown.sh</smbconfoption>
<smbconfoption name="abort shutdown script">/sbin/shutdown -c</smbconfoption>
<smbconfoption name="logon script">scripts\logon.bat</smbconfoption>
<smbconfoption name="logon path">\%L\profiles\%U</smbconfoption>
<smbconfoption name="logon drive">X:</smbconfoption>
<smbconfoption name="logon home">\%L\%U</smbconfoption>
<smbconfoption name="domain logons">Yes</smbconfoption>
<smbconfoption name="preferred master">Yes</smbconfoption>
<smbconfoption name="include">/etc/samba/common.conf</smbconfoption>
<smbconfsection name="[homes]"/>
<smbconfoption name="comment">Home Directories</smbconfoption>
<smbconfoption name="valid users">%S</smbconfoption>
<smbconfoption name="read only">No</smbconfoption>
<smbconfoption name="browseable">No</smbconfoption>
<smbconfsection name="[netlogon]"/>
<smbconfoption name="comment">Network Logon Service</smbconfoption>
<smbconfoption name="path">/var/lib/samba/netlogon</smbconfoption>
<smbconfoption name="guest ok">Yes</smbconfoption>
<smbconfoption name="locking">No</smbconfoption>
<smbconfsection name="[profiles]"/>
<smbconfoption name="comment">Profile Share</smbconfoption>
<smbconfoption name="path">/var/lib/samba/profiles</smbconfoption>
<smbconfoption name="read only">No</smbconfoption>
<smbconfoption name="profile acls">Yes</smbconfoption>
</smbconfblock>
</example>
<!-- Three -->
<example id="ch5-commonsmb">
<title>Common Samba Configuration File: <filename>/etc/samba/common.conf</filename></title>
<smbconfblock>
<smbconfsection name="[global]"/>
<smbconfoption name="username map">/etc/samba/smbusers</smbconfoption>
<smbconfoption name="log level">1</smbconfoption>
<smbconfoption name="syslog">0</smbconfoption>
<smbconfoption name="log file">/var/log/samba/%m</smbconfoption>
<smbconfoption name="max log size">50</smbconfoption>
<smbconfoption name="smb ports">139</smbconfoption>
<smbconfoption name="name resolve order">wins bcast hosts</smbconfoption>
<smbconfoption name="time server">Yes</smbconfoption>
<smbconfoption name="printcap name">CUPS</smbconfoption>
<smbconfoption name="show add printer wizard">No</smbconfoption>
<smbconfoption name="shutdown script">/var/lib/samba/scripts/shutdown.sh</smbconfoption>
<smbconfoption name="abort shutdown script">/sbin/shutdown -c</smbconfoption>
<smbconfoption name="utmp">Yes</smbconfoption>
<smbconfoption name="map acl inherit">Yes</smbconfoption>
<smbconfoption name="printing">cups</smbconfoption>
<smbconfoption name="veto files">/*.eml/*.nws/*.{*}/</smbconfoption>
<smbconfoption name="veto oplock files">/*.doc/*.xls/*.mdb/</smbconfoption>
<smbconfoption name="include"> </smbconfoption>
<smbconfcomment>Share and Service Definitions are common to all servers</smbconfcomment>
<smbconfsection name="[printers]"/>
<smbconfoption name="comment">SMB Print Spool</smbconfoption>
<smbconfoption name="path">/var/spool/samba</smbconfoption>
<smbconfoption name="guest ok">Yes</smbconfoption>
<smbconfoption name="printable">Yes</smbconfoption>
<smbconfoption name="use client driver">Yes</smbconfoption>
<smbconfoption name="default devmode">Yes</smbconfoption>
<smbconfoption name="browseable">No</smbconfoption>
<smbconfsection name="[apps]"/>
<smbconfoption name="comment">Application Files</smbconfoption>
<smbconfoption name="path">/apps</smbconfoption>
<smbconfoption name="admin users">bjordan</smbconfoption>
<smbconfoption name="read only">No</smbconfoption>
</smbconfblock>
</example>
<!-- Four -->
<example id="ch5-bldg1-smb">
<title>Server: BLDG1 (Member), File: smb.conf</title>
<smbconfblock>
<smbconfcomment>Global parameters</smbconfcomment>
<smbconfsection name="[global]"/>
<smbconfoption name="workgroup">MEGANET</smbconfoption>
<smbconfoption name="netbios name">BLDG1</smbconfoption>
<smbconfoption name="include">/etc/samba/dom-mem.conf</smbconfoption>
</smbconfblock>
</example>
<!-- Five -->
<example id="ch5-bldg2-smb">
<title>Server: BLDG2 (Member), File: smb.conf</title>
<smbconfblock>
<smbconfcomment>Global parameters</smbconfcomment>
<smbconfsection name="[global]"/>
<smbconfoption name="workgroup">MEGANET</smbconfoption>
<smbconfoption name="netbios name">BLDG2</smbconfoption>
<smbconfoption name="include">/etc/samba/dom-mem.conf</smbconfoption>
</smbconfblock>
</example>
<!-- Six -->
<example id="ch5-dommem-smb">
<title>Common Domain Member Include File: dom-mem.conf</title>
<smbconfblock>
<smbconfcomment>Global parameters</smbconfcomment>
<smbconfsection name="[global]"/>
<smbconfoption name="shutdown script">/var/lib/samba/scripts/shutdown.sh</smbconfoption>
<smbconfoption name="abort shutdown script">/sbin/shutdown -c</smbconfoption>
<smbconfoption name="preferred master">Yes</smbconfoption>
<smbconfoption name="wins server">172.16.0.1</smbconfoption>
<smbconfoption name="idmap uid">15000-20000</smbconfoption>
<smbconfoption name="idmap gid">15000-20000</smbconfoption>
<smbconfoption name="include">/etc/samba/common.conf</smbconfoption>
</smbconfblock>
</example>
<!-- Seven -->
<example id="massive-dhcp">
<title>Server: MASSIVE, File: dhcpd.conf</title>
<screen>
# Abmas Accounting Inc.
default-lease-time 86400;
max-lease-time 172800;
default-lease-time 86400;
ddns-updates on;
ddns-update-style interim;
option ntp-servers 172.16.0.1;
option domain-name "abmas.biz";
option domain-name-servers 172.16.0.1, 172.16.4.1;
option netbios-name-servers 172.16.0.1;
option netbios-node-type 8;
subnet 172.16.1.0 netmask 255.255.252.0 {
range dynamic-bootp 172.16.1.0 172.16.2.255;
option subnet-mask 255.255.252.0;
option routers 172.16.0.1, 172.16.0.128;
allow unknown-clients;
}
subnet 172.16.4.0 netmask 255.255.252.0 {
range dynamic-bootp 172.16.7.0 172.16.7.254;
option subnet-mask 255.255.252.0;
option routers 172.16.4.128;
allow unknown-clients;
}
subnet 172.16.8.0 netmask 255.255.252.0 {
range dynamic-bootp 172.16.11.0 172.16.11.254;
option subnet-mask 255.255.252.0;
option routers 172.16.4.128;
allow unknown-clients;
}
subnet 127.0.0.0 netmask 255.0.0.0 {
}
subnet 123.45.67.64 netmask 255.255.255.252 {
}
</screen>
</example>
<!-- Eight -->
<example id="bldg1dhcp">
<title>Server: BLDG1, File: dhcpd.conf</title>
<screen>
# Abmas Accounting Inc.
default-lease-time 86400;
max-lease-time 172800;
default-lease-time 86400;
ddns-updates on;
ddns-update-style ad-hoc;
option ntp-servers 172.16.0.1;
option domain-name "abmas.biz";
option domain-name-servers 172.16.0.1, 172.16.4.1;
option netbios-name-servers 172.16.0.1;
option netbios-node-type 8;
subnet 172.16.1.0 netmask 255.255.252.0 {
range dynamic-bootp 172.16.3.0 172.16.3.255;
option subnet-mask 255.255.252.0;
option routers 172.16.0.1, 172.16.0.128;
allow unknown-clients;
}
subnet 172.16.4.0 netmask 255.255.252.0 {
range dynamic-bootp 172.16.5.0 172.16.6.255;
option subnet-mask 255.255.252.0;
option routers 172.16.4.128;
allow unknown-clients;
}
subnet 127.0.0.0 netmask 255.0.0.0 {
}
</screen>
</example>
<!-- Nine -->
<example id="bldg2dhcp">
<title>Server: BLDG2, File: dhcpd.conf</title>
<screen>
# Abmas Accounting Inc.
default-lease-time 86400;
max-lease-time 172800;
default-lease-time 86400;
ddns-updates on;
ddns-update-style interim;
option ntp-servers 172.16.0.1;
option domain-name "abmas.biz";
option domain-name-servers 172.16.0.1, 172.16.4.1;
option netbios-name-servers 172.16.0.1;
option netbios-node-type 8;
subnet 172.16.8.0 netmask 255.255.252.0 {
range dynamic-bootp 172.16.9.0 172.16.10.255;
option subnet-mask 255.255.252.0;
option routers 172.16.8.128;
allow unknown-clients;
}
subnet 127.0.0.0 netmask 255.0.0.0 {
}
</screen>
</example>
<!-- Ten -->
<example id="massive-nameda">
<title>Server: MASSIVE, File: named.conf, Part: A</title>
<screen>
###
# Abmas Biz DNS Control File
###
# Date: November 15, 2003
###
options {
directory "/var/lib/named";
forwarders {
123.45.12.23;
123.45.54.32;
};
forward first;
listen-on {
mynet;
};
auth-nxdomain yes;
multiple-cnames yes;
notify no;
};
zone "." in {
type hint;
file "root.hint";
};
zone "localhost" in {
type master;
file "localhost.zone";
};
zone "0.0.127.in-addr.arpa" in {
type master;
file "127.0.0.zone";
};
acl mynet {
172.16.0.0/24;
172.16.4.0/24;
172.16.8.0/24;
127.0.0.1;
};
acl seconddns {
123.45.54.32;
};
</screen>
</example>
<!-- Eleven -->
<example id="massive-namedb">
<title>Server: MASSIVE, File: named.conf, Part: B</title>
<screen>
zone "abmas.biz" {
type master;
file "/var/lib/named/master/abmas.biz.hosts";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
allow-update {
mynet;
};
};
zone "abmas.us" {
type master;
file "/var/lib/named/master/abmas.us.hosts";
allow-query {
all;
};
allow-transfer {
seconddns;
};
};
</screen>
</example>
<!-- Twelve -->
<example id="massive-namedc">
<title>Server: MASSIVE, File: named.conf, Part: C</title>
<screen>
zone "0.16.172.in-addr.arpa" {
type master;
file "/var/lib/named/master/172.16.0.0.rev";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
allow-update {
mynet;
};
};
zone "4.16.172.in-addr.arpa" {
type master;
file "/var/lib/named/master/172.16.4.0.rev";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
allow-update {
mynet;
};
};
zone "8.16.172.in-addr.arpa" {
type master;
file "/var/lib/named/master/172.16.8.0.rev";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
allow-update {
mynet;
};
};
</screen>
</example>
<!-- Thirteen -->
<example id="abmasbizdns">
<title>Forward Zone File: abmas.biz.hosts</title>
<screen>
$ORIGIN .
$TTL 38400 ; 10 hours 40 minutes
abmas.biz IN SOA massive.abmas.biz. root.abmas.biz. (
2003021833 ; serial
10800 ; refresh (3 hours)
3600 ; retry (1 hour)
604800 ; expire (1 week)
38400 ; minimum (10 hours 40 minutes)
)
NS massive.abmas.biz.
NS bldg1.abmas.biz.
NS bldg2.abmas.biz.
MX 10 massive.abmas.biz.
$ORIGIN abmas.biz.
massive A 172.16.0.1
router0 A 172.16.0.128
bldg1 A 172.16.4.1
router4 A 172.16.4.128
bldg2 A 172.16.8.1
router8 A 172.16.8.128
</screen>
</example>
<!-- Forteen -->
<example id="abmasusdns">
<title>Forward Zone File: abmas.biz.hosts</title>
<screen>
$ORIGIN .
$TTL 38400 ; 10 hours 40 minutes
abmas.us IN SOA server.abmas.us. root.abmas.us. (
2003021833 ; serial
10800 ; refresh (3 hours)
3600 ; retry (1 hour)
604800 ; expire (1 week)
38400 ; minimum (10 hours 40 minutes)
)
NS dns.abmas.us.
NS dns2.abmas.us.
MX 10 mail.abmas.us.
$ORIGIN abmas.us.
server A 123.45.67.66
dns2 A 123.45.54.32
gw A 123.45.67.65
www CNAME server
mail CNAME server
dns CNAME server
</screen>
</example>
<!-- Fifteen -->
<example id="bldg12nameda">
<title>Servers: BLDG1/BLDG2, File: named.conf, Part: A</title>
<screen>
###
# Abmas Biz DNS Control File
###
# Date: November 15, 2003
###
options {
directory "/var/lib/named";
forwarders {
172.16.0.1;
};
forward first;
listen-on {
mynet;
};
auth-nxdomain yes;
multiple-cnames yes;
notify no;
};
zone "." in {
type hint;
file "root.hint";
};
zone "localhost" in {
type master;
file "localhost.zone";
};
zone "0.0.127.in-addr.arpa" in {
type master;
file "127.0.0.zone";
};
acl mynet {
172.16.0.0/24;
172.16.4.0/24;
172.16.8.0/24;
127.0.0.1;
};
acl seconddns {
123.45.54.32;
};
</screen>
</example>
<!-- Sixteen -->
<example id="bldg12namedb">
<title>Servers: BLDG1/BLDG2, File: named.conf, Part: B</title>
<screen>
zone "abmas.biz" {
type slave;
file "/var/lib/named/slave/abmas.biz.hosts";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
};
zone "0.16.172.in-addr.arpa" {
type slave;
file "/var/lib/slave/master/172.16.0.0.rev";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
};
zone "4.16.172.in-addr.arpa" {
type slave;
file "/var/lib/named/slave/172.16.4.0.rev";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
};
zone "8.16.172.in-addr.arpa" {
type slave;
file "/var/lib/named/slave/172.16.8.0.rev";
allow-query {
mynet;
};
allow-transfer {
mynet;
};
};
</screen>
</example>
<!-- Seventeen -->
<example id="ch5-initgrps">
<title>Initialize Groups Script, File: /etc/samba/initGrps.sh</title>
<screen>
#!/bin/bash
# Create UNIX groups
groupadd acctsdep
groupadd finsrvcs
groupadd piops
# Map Windows Domain Groups to UNIX groups
net groupmap add ntgroup="Domain Admins" unixgroup=root type=d
net groupmap add ntgroup="Domain Users" unixgroup=users type=d
net groupmap add ntgroup="Domain Guests" unixgroup=nobody type=d
# Add Functional Domain Groups
net groupmap add ntgroup="Accounts Dept" unixgroup=acctsdep type=d
net groupmap add ntgroup="Financial Services" unixgroup=finsrvcs type=d
net groupmap add ntgroup="Insurance Group" unixgroup=piops type=d
</screen>
</example>
<!-- End of Examples -->
<sect2 id="ch5-procstart">
<title>Process Startup Configuration</title>
<para>
<indexterm><primary>chkconfig</primary></indexterm>
<indexterm><primary>daemon control</primary></indexterm>
There are two essential steps to process startup configuration. A process
must be configured so that it is automatically restarted each time the server
is rebooted. This step involves use of the <command>chkconfig</command> tool that
created appropriate symbolic links from the master daemon control file that is
located in the <filename>/etc/rc.d</filename> directory to the <filename>/etc/rc'x'.d</filename>
directories. Links are created so that when the system run-level is changed, the
necessary start or kill script is run.
</para>
<para>
<indexterm><primary>/etc/xinetd.d</primary></indexterm>
In the event that a service is provided not as a daemon but via the internetworking
super daemon (<command>inetd</command> or <command>xinetd</command>), then the <command>chkconfig</command>
tool makes the necessary entries in the <filename>/etc/xinetd.d</filename> directory
and sends a hang-up (HUP) signal to the super daemon, thus forcing it to
re-read its control files.
</para>
<para>
Last, each service must be started to permit system validation to proceed. The following steps
are for a Red Hat Linux system, please adapt them to suit the target OS platform on which you
are installing Samba.
</para>
<procedure>
<title>Process Startup Configuration Steps</title>
<step><para>
Use the standard system tool to configure each service to restart
automatically at every system reboot. For example,
<indexterm><primary>chkconfig</primary></indexterm>
<screen>
&rootprompt; chkconfig dhpc on
&rootprompt; chkconfig named on
&rootprompt; chkconfig cups on
&rootprompt; chkconfig smb on
&rootprompt; chkconfig swat on
</screen>
</para></step>
<step><para>
<indexterm><primary>starting dhcpd</primary></indexterm>
<indexterm><primary>starting samba</primary></indexterm>
<indexterm><primary>starting CUPS</primary></indexterm>
Now start each service to permit the system to be validated.
Execute each of the following in the sequence shown:
<screen>
&rootprompt; service dhcp restart
&rootprompt; service named restart
&rootprompt; service cups restart
&rootprompt; service smb restart
&rootprompt; service swat restart
</screen>
</para></step>
</procedure>
</sect2>
<sect2 id="ch5wincfg">
<title>Windows Client Configuration</title>
<para>
The procedure for desktop client configuration for the network in this chapter is similar to
that used for the previous one. There are a few subtle changes that should be noted.
</para>
<procedure>
<title>Windows Client Configuration Steps</title>
<step><para>
Install MS Windows XP Professional. During installation, configure the client to use DHCP for
TCP/IP protocol configuration.
<indexterm><primary>WINS</primary></indexterm>
<indexterm><primary>DHCP</primary></indexterm>
DHCP configures all Windows clients to use the WINS Server address that has been defined
for the local subnet.
</para></step>
<step><para>
Join the Windows domain <constant>MEGANET</constant>. Use the domain administrator
username <constant>root</constant> and the SMB password you assigned to this account.
A detailed step-by-step procedure for joining a Windows 200x/XP Professional client to
a Windows domain is given in <link linkend="appendix"/>, <link linkend="domjoin"/>.
Reboot the machine as prompted and then log on using the domain administrator account
(<constant>root</constant>).
</para></step>
<step><para>
Verify that the server called <constant>MEGANET</constant> is visible in <guimenu>My Network Places</guimenu>,
that it is possible to connect to it and see the shares <guimenuitem>accounts</guimenuitem>,
<guimenuitem>apps</guimenuitem>, and <guimenuitem>finsvcs</guimenuitem>,
and that it is possible to open each share to reveal its contents.
</para></step>
<step><para>
Create a drive mapping to the <constant>apps</constant> share on a server. At this time, it does
not particularly matter which application server is used. It is necessary to manually
set a persistent drive mapping to the local applications server on each workstation at the time of
installation. This step is avoided by the improvements to the design of the network configuration
in the next chapter.
</para></step>
<step><para>
Perform an administrative installation of each application to be used. Select the options
that you wish to use. Of course, you choose to run applications over the network, correct?
</para></step>
<step><para>
Now install all applications to be installed locally. Typical tools include Adobe Acrobat,
NTP-based time synchronization software, drivers for specific local devices such as fingerprint
scanners, and the like. Probably the most significant application to be locally installed
is antivirus software.
</para></step>
<step><para>
Now install all four printers onto the staging system. The printers you install
include the accounting department HP LaserJet 6 and Minolta QMS Magicolor printers, and you
also configure use of the identical printers that are located in the financial services department.
Install printers on each machine using the following steps:
</para>
<procedure>
<title>Steps to Install Printer Drivers on Windows Clients</title>
<step><para>
Click <menuchoice>
<guimenu>Start</guimenu>
<guimenuitem>Settings</guimenuitem>
<guimenuitem>Printers</guimenuitem>
<guiicon>Add Printer</guiicon>
<guibutton>Next</guibutton>
</menuchoice>. Do not click <guimenuitem>Network printer</guimenuitem>.
Ensure that <guimenuitem>Local printer</guimenuitem> is selected.
</para></step>
<step><para>
Click <guibutton>Next</guibutton>. In the
<guimenuitem>Manufacturer:</guimenuitem> panel, select <constant>HP</constant>.
In the <guimenuitem>Printers:</guimenuitem> panel, select the printer called
<constant>HP LaserJet 6</constant>. Click <guibutton>Next</guibutton>.
</para></step>
<step><para>
In the <guimenuitem>Available ports:</guimenuitem> panel, select
<constant>FILE:</constant>. Accept the default printer name by clicking
<guibutton>Next</guibutton>. When asked, <quote>Would you like to print a
test page?</quote>, click <guimenuitem>No</guimenuitem>. Click
<guibutton>Finish</guibutton>.
</para></step>
<step><para>
You may be prompted for the name of a file to print to. If so, close the
dialog panel. Right-click <menuchoice>
<guiicon>HP LaserJet 6</guiicon>
<guimenuitem>Properties</guimenuitem>
<guisubmenu>Details (Tab)</guisubmenu>
<guibutton>Add Port</guibutton>
</menuchoice>.
</para></step>
<step><para>
In the <guimenuitem>Network</guimenuitem> panel, enter the name of
the print queue on the Samba server as follows: <constant>\\BLDG1\hplj6a</constant>.
Click <menuchoice>
<guibutton>OK</guibutton>
<guibutton>OK</guibutton>
</menuchoice> to complete the installation.
</para></step>
<step><para>
Repeat the printer installation steps above for both HP LaserJet 6 printers
as well as for both QMS Magicolor laser printers. Remember to install all
printers but to set the destination port for each to the server on the
local network. For example, a workstation in the accounting group should
have all printers directed at the server <constant>BLDG1</constant>.
You may elect to point all desktop workstation configurations at the
server called <constant>MASSIVE</constant> and then in your deployment
procedures, it would be wise to document the need to redirect the printer
configuration (as well as the applications server drive mapping) to the
server on the network segment on which the workstation is to be located.
</para></step>
</procedure>
</step>
<step><para>
When you are satisfied that the staging systems are complete, use the appropriate procedure to
remove the client from the domain. Reboot the system, and then log on as the local administrator
and clean out all temporary files stored on the system. Before shutting down, use the disk
defragmentation tool so that the file system is in optimal condition before replication.
</para></step>
<step><para>
Boot the workstation using the Norton (Symantec) Ghosting disk (or CD-ROM) and image the
machine to a network share on the server.
</para></step>
<step><para>
You may now replicate the image using the appropriate Norton Ghost procedure to the target
machines. Make sure to use the procedure that ensures each machine has a unique
Windows security identifier (SID). When the installation of the disk image is complete, boot the PC.
</para></step>
<step><para>
Log onto the machine as the local Administrator (the only option), and join the machine to
the domain following the procedure set out in <link linkend="appendix"/>, <link linkend="domjoin"/>. You must now set the
persistent drive mapping to the applications server that the user is to use. The system is now
ready for the user to log on, provided you have created a network logon account for that
user, of course.
</para></step>
<step><para>
Instruct all users to log onto the workstation using their assigned username and password.
</para></step>
</procedure>
</sect2>
<sect2>
<title>Key Points Learned</title>
<para>
The network you have just deployed has been a valuable exercise in forced constraint.
You have deployed a network that works well, although you may soon start to see
performance problems, at which time the modifications demonstrated in <link linkend="happy"/>
bring the network to life. The following key learning points were experienced:
</para>
<itemizedlist>
<listitem><para>
The power of using &smb.conf; include files
</para></listitem>
<listitem><para>
Use of a single PDC over a routed network
</para></listitem>
<listitem><para>
Joining a Samba-3 domain member server to a Samba-3 domain
</para></listitem>
<listitem><para>
Configuration of winbind to use domain users and groups for Samba access
to resources on the domain member servers
</para></listitem>
<listitem><para>
The introduction of roaming profiles
</para></listitem>
</itemizedlist>
</sect2>
</sect1>
<sect1>
<title>Questions and Answers</title>
<para>
</para>
<qandaset defaultlabel="chap01qa" type="number">
<qandaentry>
<question>
<para>
The example &smb.conf; files in this chapter make use of the <parameter>include</parameter> facility.
How may I get to see what the actual working &smb.conf; settings are?
</para>
</question>
<answer>
<para>
You may readily see the net compound effect of the included files by running:
<screen>
&rootprompt; testparm -s | less
</screen>
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
Why does the include file <filename>common.conf</filename> have an empty include statement?
</para>
</question>
<answer>
<para>
The use of the empty include statement nullifies further includes. For example, let's say you
desire to have just an smb.conf file that is built from the array of include files of which the
master control file is called <filename>master.conf</filename>. The following command
produces a compound &smb.conf; file.
<screen>
&rootprompt; testparm -s /etc/samba/master.conf > /etc/samba/smb.conf
</screen>
If the include parameter was not in the common.conf file, the final &smb.conf; file leaves
the include in place, even though the file it points to has already been included. This is a bug
that will be fixed at a future date.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
I accept that the simplest configuration necessary to do the job is the best. The use of <parameter>tdbsam</parameter>
passdb backend is much simpler than having to manage an LDAP-based <parameter>ldapsam</parameter> passdb backend.
I tried using <command>rsync</command> to replicate the <filename>passdb.tdb</filename>, and it seems to work fine!
So what is the problem?
</para>
</question>
<answer>
<para>
Replication of the <parameter>tdbsam</parameter> database file can result in loss of currency in its
contents between the PDC and BDCs. The most notable symptom is that workstations may not be able
to log onto the network following a reboot and may have to rejoin the domain to recover network
access capability.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
You are using DHCP Relay enabled on the routers as well as a local DHCP server. Will this cause a clash?
</para>
</question>
<answer>
<para>
No. It is possible to have as many DHCP servers on a network segment as makes sense. A DHCP server
offers an IP address lease, but it is the client that determines which offer is accepted, no matter how many
offers are made. Under normal operation, the client accepts the first offer it receives.
</para>
<para>
The only exception to this rule is when the client makes a directed request from a specific DHCP server
for renewal of the lease it has. This means that under normal circumstances there is no risk of a clash.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
How does the Windows client find the PDC?
</para>
</question>
<answer>
<para>
The Windows client obtains the WINS server address from the DHCP lease information. It also
obtains from the DHCP lease information the parameter that causes it to use directed UDP (UDP Unicast)
to register itself with the WINS server and to obtain enumeration of vital network information to
enable it to operate successfully.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
Why did you enable IP forwarding (routing) only on the server called <constant>MASSIVE</constant>?
</para>
</question>
<answer>
<para>
The server called <constant>MASSIVE</constant> is acting as a router to the Internet. No other server
(BLDG1 or BLDG2) has any need for IP forwarding because they are attached only to their own network.
Route table entries are needed to direct MASSIVE to send all traffic intended for the remote network
segments to the router that is its gateway to them.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
You did nothing special to implement roaming profiles. Why?
</para>
</question>
<answer>
<para>
Unless configured to do otherwise, the default behavior with Samba-3 and Windows XP Professional
clients is to use roaming profiles.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
On the domain member computers, you configured winbind in the <filename>/etc/nsswitch.conf</filename> file.
You did not configure any PAM settings. Is this an omission?
</para>
</question>
<answer>
<para>
PAM is needed only for authentication. When Samba is using Microsoft encrypted passwords, it makes only
marginal use of PAM. PAM configuration handles only authentication. If you want to log onto the domain
member servers using Windows networking usernames and passwords, it is necessary to configure PAM
to enable the use of winbind. Samba makes use only of the identity resolution facilities of the name
service switch (NSS).
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
You are starting SWAT up on this example but have not discussed that anywhere. Why did you do this?
</para>
</question>
<answer>
<para>
Oh, I did not think you would notice that. It is there so that it can be used. This is more fully discussed
in <emphasis>TOSHARG2</emphasis>, which has a full chapter dedicated to the subject. While we are on the
subject, it should be noted that you should definitely not use SWAT on any system that makes use
of &smb.conf; <parameter>include</parameter> files because SWAT optimizes them out into an aggregated
file but leaves in place a broken reference to the top-layer include file. SWAT was not designed to
handle this functionality gracefully.
</para>
</answer>
</qandaentry>
<qandaentry>
<question>
<para>
The domain controller has an auto-shutdown script. Isn't that dangerous?
</para>
</question>
<answer>
<para>
Well done, you spotted that! I guess it is dangerous. It is good to know that you can do this, though.
</para>
</answer>
</qandaentry>
</qandaset>
</sect1>
</chapter>